Auto merge of #22844 - paulrouget:capi-header, r=SimonSapin

Generate simpleservo.h

Fix #22834

Waiting on https://github.com/eqrion/cbindgen/pull/271

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ports/libsimpleservo/capi/Cargo.toml

@@ -17,6 +17,9 @@ simpleservo = { path = "../api" }
 log = "0.4"
 env_logger = "0.6"
 
+[build-dependencies]
+cbindgen = "0.8"
+
 [features]
 default = ["unstable", "default-except-unstable"]
 default-except-unstable = ["webdriver", "max_log_level"]

ports/libsimpleservo/capi/build.rs

@@ -0,0 +1,18 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+use std::env;
+
+fn main() {
+    let crate_dir = env::var("CARGO_MANIFEST_DIR").unwrap();
+    let target_dir = env::var("CARGO_TARGET_DIR").unwrap();
+    let profile_dir = env::var("PROFILE").unwrap();
+    let dest = format!("{}/{}/{}", target_dir, profile_dir, "simpleservo.h");
+    cbindgen::Builder::new()
+        .with_crate(crate_dir)
+        .with_language(cbindgen::Language::C)
+        .generate()
+        .expect("Unable to generate bindings")
+        .write_to_file(dest);
+}